In recent years, the portable personal minicomputers (movable computers) below the size of B5 or B6 and personal digital assistants (PDA) have gotten a rapid popularization. As a ┌press key Input┘ has become a handicap of machine miniaturization, a stroke input mode by touching a liquid crystal screen with a pen has been popular.
Generally, the stroke input mode has two types: a ┌hand write input┘ writing characters directly on a plate; and a ┌soft keyboard input┘ for inputting characters by touching a small virtual keyboard in a display screen with a pen.
Neither of the two types uses a physical (substantial) keyboard, and this facilitates the miniaturization of the machine for portability.
Yet, there are several problems for the input mode using a pen: the ┌hand write input┘ provides some advantages for people, who hate key-board input, but it is not fit for the occasion that requires rapid input and long-time input for the character inputting and character judging are exceedingly time-consuming.
In addition, the virtual keyboard for the ┌soft keyboard input┘ commonly is set with one character for each press key respectively, so the press keys are very fine, crowded, and difficult to touch. For example: there are 26 letters in English, so it needs 26 press keys correspondingly, and more press keys are required in Japanese, Chinese, Korean and other languages, such as in Japanese, 50 kana need corresponding 50 press keys.
If so many press keys are displayed in a limited area, the sizes of the press keys have to be reduced. Therefore, the ┌soft keyboard input┘ also has the problems such as inconvenient input operation, inapplicability for the occasion that requires rapid and long-time input and so on.